Hydraulic setting mixture for materials having “easy-to-clean” properties

ABSTRACT

The present invention relates to a hydraulic setting mixture comprising: a) 6% to 25% by weight of cement, b) 50% to 90% by weight of at least one aggregate, and c) 0.001% to 8% by weight of at least one fluoroorganyl-substituted silicon compound, and also to materials produced from this mixture, more particularly components, concrete articles or mouldings. The invention further relates to the use of a hydraulic setting mixture of the invention for producing materials, more particularly components, concrete articles or mouldings, for example as face concrete, where the surface of the materials exhibits only relatively low soiling tendency (“easy-to-clean” property) even on abrasion.

The present invention relates to a specific hydraulically settingmixture such that a set or cured workpiece produced therefrom hasdirt-repellant properties on the surface.

Hydraulically setting materials, for example cement-bonded materials,are used in numerous relevant places in modern building andconstruction, for example for the use of concrete paving slabs fordriveways, footpaths/sidewalks or terraces. In the exterior sector inparticular, soiling of the surfaces of such concrete paving slabs by awide variety of materials, for example exhaust gases from traffic andindustry, in particular soot, flower pollen, grass stains, oils, inparticular motor oils, beverage and food residues, in particular cola,coffee, red wine or ketchup, and also as a result of the growth ofmicroorganisms such as algae or fungi, is a great problem from anesthetic point of view. Given hydraulically set materials in suchapplications dirt-repellent properties [hereinafter also referred to as“easy-to-clean” or ETC] is therefore desirable.

The expression “dirt-repellent properties” refers to the ability of thesurface to prevent intrusion of both aqueous and oily substances intothe material and make removal of these substances from the surfaceeasier.

It is known that easy-to-clean properties can be produced byafter-treatment of finished, cured surfaces with various materials.Thus, inter alia, EP 0 838 467 teaches the use of a fluorine-containingsilane or silane system for upgrading the surface. Disadvantages of suchsystems for the after-treatment of a surface are, firstly, the necessityof a further process step after production of such materials and,secondly, the durability of such coatings is frequently too low sincethey are detached as a result of weathering and abrasion.

It is also known that hydraulically cured materials, in particularcement-bonded materials, can be improved by addition of body modifiers.Thus, EP 0 913 370 teaches the use of aqueous, silane-containingemulsions for achieving water-repellant (hydrophobic) properties of suchmaterials. Unfortunately, the teaching does not lead to the desiredeasy-to-clean surfaces.

U.S. Pat. No. 5,650,004 discloses a cement-bonded render mixture whichis used for sealing of swimming pools. The water-repellent propertiesand improved durability of the render mixture are achieved by additionof silane-modified powders and pozzolanic fillers. A disadvantage ofthis render mixture is that although long-term water-repellentproperties can be achieved, i.e. aqueous soiling can also be repelled,dirt-repellent properties in the above-described sense cannot beachieved.

DE 10 346 082 discloses hydraulically curing mixtures whose specificcomposition leads to an altered microstructure. This giveswear-resistant workpieces having surfaces which are to some extentdirt-repellent.

EP 1 445 242 discloses non-cement-bonded renders and coatings forexterior walls, which renders/coatings have dirt-repellent properties.The dirt-repellent properties are achieved by reducing themicroroughness in such a way that dirt particles cannot penetrate intothe pores and settle there. A disadvantage is that non-cement-bondedrender mixtures based on potassium water glass are modified as such.

It was an object of the present invention to provide a furtherhydraulically setting mixture, in particular cement-bonded mixture,which is such that the surface of a material produced therefrom hassufficiently good dirt-repellent properties after setting or curing andthese are very durable.

This object is achieved according to the invention by the features ofthe claims.

It has now surprisingly been found that the addition of at least onefluoroorganyl-substituted silicon compound, in particular afluoroorganyl-substituted silane and/or fluoroorganyl-substitutedsiloxane, to a hydraulically setting mixture, in particular an otherwiseconventional concrete mixture, enables durable ETC properties of ahydraulically set and cured material produced therefrom to be achieved.

The present invention accordingly provides a hydraulically settingmixture, in particular for materials having easy-to-clean properties,comprising:

-   -   a) from 6 to 25% by weight, preferably from 10 to 20% b_(y)        weight, particularly preferably from 12 to 18% by weight, of        cement,    -   b) from 50 to 90% by weight, preferably from 65 to 85% by        weight, particularly preferably from 70 to 80% by weight, of at        least one aggregate and    -   c) from 0.001 to 8% by weight, preferably from 0.003 to 5% by        weight, particularly preferably from 0.005 to 2% by weight, very        particularly preferably from 0.01 to 2% by weight, in particular        from 0.05 to 2% by weight, of at least one        fluoroorganyl-substituted silicon compound.

Here, the mixture of constituents or components used in each case add upto 100% by weight.

It is provided that, depending on the specific choice of mixtureconstituents in each case, the general amount limits specified under a),b) and c) be adhered to.

The fluoroorganyl-substituted silicon compounds used according to theinvention are preferably selected from the group consisting offluoroorganyl-substituted silanes and fluoroorganyl-substitutedsiloxanes and mixtures thereof. In particular, they are preferablyselected from the group consisting of monomeric fluoroalkyl-substitutedsilanes and fluoroalkyl-substituted siloxanes and mixtures thereof.Preferred examples of monomeric fluoroalkyl-substituted silanes are3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyltriethoxysilane and3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyltrimethoxysilane. Accordingto the invention, preparations based on mixtures based on at least oneabovementioned monomeric fluoroalkyl-substituted silane orfluoroalkyl-substituted siloxanes and optionally at least one furtherorganosilane or organosiloxane, in particular aC₁-C₁₆-alkyltrialkoxysilane, for example methyl-, propyl-, butyl-,octyl-, hexadecyltrimethoxysilane or -triethoxysilane, to name only afew, or an oligomeric organoalkoxysilane can also be appropriately usedas fluoroorganyl-substituted silicon compounds, where such preparationsare selected from the group consisting of water-, alcohol- and/orhydrocarbon-containing solutions or emulsions. Such preparations are,for example but not exclusively, to be found in DE 196 06 011, EP 0 538555, EP 0 675 128, EP 0 716 127, EP 0 716 128,

EP 0 832 911, EP 0 846 717, EP 0 953 591, EP 0 960 921, EP 1 033 395, EP1 101 787, EP 1 193 302, WO 2006/010666, WO 2006/010388, WO 2009/030538.

An additional advantage of the fluoroorganyl-substituted siliconcompounds used according to the invention is that silanes often have afluidizing effect on preparations. The fluoroorgano systems used heresurprisingly do not have an adverse effect on the green solidity.

In addition, a hydraulically setting mixture according to the inventioncan advantageously additionally comprise, as further components,

-   -   d) from 0.01 to 2% by weight, preferably from 0.05 to 0.5% by        weight, of plasticizers, and/or    -   e) from 0.01 to 1% by weight of at least one further auxiliary.

As cement, all customary cements selected from the group consisting ofportland cements, composite cements, cements having proportions ofpozzolans such as fly ash or microsilica and blast furnace cements canbe used or present in a mixture according to the invention. Thus, thecement in a mixture according to the invention is preferably, but notexclusively, selected from the group consisting of portland cements,composite cements and blast furnace cements.

Aggregates in a mixture according to the invention can be, for example,rock particle size fractions in accordance with EN 206-1:2000. Inparticular, aggregates can be agglomerates, sands, gravels, crushedmaterial, porphyry, quartz flour, ground limestone and ground rock ormixtures thereof, and also fly ashes, microsilica and other siliceousadditives or mixtures thereof. Here, sands can be, for example, silicasands or river sands. Preference is given to gravels, crushed material,crushed sands, porphyry, quartz flour, ground limestone and ground rockor mixtures thereof. Thus, a mixture according to the invention canadvantageously contain aggregates which preferably have a maximumparticle size of from 8 to 63 mm particularly preferably 8 mm, 16 mm, 32mm or 63 mm, in particular aggregates having a maximum particle size of32 mm, in accordance with DIN 1045-2. Particular preference is given tothe aggregate being an agglomerate having a maximum particle size of 32mm and/or sand having a maximum particle size of 5 mm.

Thus, a mixture according to the invention can generally be produced ina simple and economical way by combining and mixing the componentsaccording to the claims. Thus, a mixture according to the invention cantypically be admixed with water and mixed in a mixing apparatus. Ingeneral, a hydraulically setting mixture can firstly be provided bymixing of the components according to the present main claim. Furthercomponents, which have been listed above, can be added to this mixturewhen it is combined with an amount of water according to the claimduring use, optionally with good mixing using apparatuses or vesselsknown per se to those skilled in the art, and the resulting mixture or acomposition produced in this way can be introduced into a desired moldand allowed to hydraulically set and cure.

Fluoroorganyl-substituted silicon compounds according to the inventioncan be (i) compounds derived from the general formulae I, II, III, IVand/or V and can have crosslinking structural elements which formchain-like, cyclic, crosslinked and/or three-dimensionally crosslinkedstructures, where at least one structure in idealized form correspondsto the general formula I(HO)[(HO)_(1-x)(R²)_(x)Si(A)O]_(a)[Si(B)(R³)_(y)(OH)_(1-y)O]_(b)[Si(C)(R⁵)_(u)(OH)_(1-u)O]_(c)[Si(D)(OH)O]_(d)H·(HX)_(e)  (I),where, in formula I, the structural elements are derived fromalkoxysilane of the general formulae II, III, IV and/or V and

-   -   A corresponds to an aminoalkyl radical        H₂N(CH₂)_(f)(NH)_(g)(CH₂)_(h)(NH)_(m)(R⁷)_(n−) in the structural        element derived from the general formula II,        H₂N(CH₂)_(f)(NH)_(g)(CH₂)_(h)(NH)_(m)(R⁷)_(n)Si(OR¹)_(3-x)(R²)_(x)          (II),        where f is an integer in the range from 0 to 6, where g=0 when        f=0 and g=1 when f>0, h is an integer in the range from 0 to 6,        x=0 or 1, m=0 or 1 and n=0 or 1, where n+m=0 or 2 in formula II,        and R⁷ is a linear, branched or cyclic divalent alkyl group        having from 1 to 16 carbon atoms,    -   B corresponds to a fluoroalkyl radical R⁴—Y—(CH₂)_(k)-in the        structural element derived from the general formula III,        R⁴—Y—(CH₂)_(k)Si(R³)_(y)(OR¹)_(3-y)   (III),        where R⁴ is a monofluorinated, oligofluorinated or        perfluorinated alkyl group having from 1 to 9 carbon atoms or a        monofluorinated, oligofluorinated or perfluorinated aryl group,        Y is a CH₂, O or S group, R³ is a linear, branched or cyclic        alkyl group having from 1 to 8 carbon atoms or an aryl group,        k=0, 1 or 2 and y=0 or 1 in formula III and/or VI, R⁴ is        preferably F₃C(CF₂)_(r−), where r=0 to 18, preferably r=5, where        Y is a CH₂ or O group, and k is preferably 1 with Y=—CH₂-,    -   C corresponds to an alkyl radical R⁵-in the structural element        derived from the general formula IV,        R⁶—Si(R⁵)_(u)(OR¹)_(3-u)   (IV),        where R⁵ is a linear or branched alkyl group having from 1 to 4        carbon atoms, in particular methyl, and u=0 or 1 in formula IV,    -   D corresponds to an alkyl radical R⁶-in the structural element        derived from the general formula V,        R⁶—Si(OR¹)₃   (V),        where R⁶ in the abovementioned formulae is a linear, branched or        cyclic alkyl group having from 1 to 8 carbon atoms and    -   the radicals R¹ in the formulae II, III, IV, V and/or VI are        each, independently of one another, a linear, branched or cyclic        alkyl group having from 1 to 8 carbon atoms or an aryl group,        and R¹ is preferably, independently, methyl, ethyl or propyl;        where R², R³ and/or R⁵ in the abovementioned formulae each        correspond, independently of one another, to a linear or        branched alkyl radical having from 1 to 4 carbon atoms,        preferably independently of one another methyl or ethyl, and    -   in formula (I), HX is an acid, where X is an inorganic or        organic acid radical, where x, y and u are each, independently        of one another, 0 or 1 and a, b, c, d and e are each,        independently of one another, integers where a≧0, b≧0, c≧0, d≧0,        e≧0 and (a+b+c+d)≧2, preferably (a+b+c+d)≧4, particularly        preferably (a+b+c+d)≧10, where X is, for example, chloride,        nitrate, formate or acetate,        or (ii) compounds in which the organosiloxanes are cocondensates        or block cocondensates or mixtures of these derived from at        least two of the abovementioned alkoxysilanes of the general        formulae II, III, IV and V, preferably derived in a molar ratio        of 1:≦3.5 from the formulae II and III or else where a, b, c and        d in the mole of the alkoxysilanes of the formulae II, III, IV        and V with a molar ratio of 0.1≦[a/b+c+d], in particular        0.25≦[a/b+c+d]≧6000, preferably 1≦[a/b+c+d]≦3 where a>0, b>0,        c≧0 and d≧0,        or (iii) monomeric fluoroorganyl-substituted silicon compounds        of the general formula VI        R⁴—Y—(CH₂)_(k)Si(R³)_(y)(OR¹)_(3−y)   (VI),        where R⁴, Y, R¹, R³, k and y are as defined above, and/or        mixtures of a plurality of monomeric compounds of the general        formula VI.

Said fluoroorganyl-substituted silicon compounds can advantageously alsobe used in the form of an aqueous preparation, e.g. as aqueous solution,dispersion or emulsion. The processability in aqueous, cement-containingmixtures can be additionally simplified in this way. Such aqueouspreparations can be, in particular, aqueous dispersions or emulsions ofa fluoroorganyl-substituted silane and/or siloxane which have a totalcontent of fluoroorganyl-substituted silicon compound of from 1.5% byweight to 90% by weight, preferably from 2% by weight to 80% by weight,particularly preferably from 2.5% by weight to 70% by weight, veryparticularly preferably from 5% by weight to 60% by weight (in each casebased on the total mass of the aqueous formulations).

If fluoroorganyl-substituted silicon compounds used according to theinvention are present in the form of an aqueous emulsion, this cancontain at least one emulsifier which is advantageously selected fromthe group consisting of alkylsulfates having C₈-C₁₈-alkyl, alkyl andalkaryl ether sulfates having C₈-C₁₈-alkyl in the hydrophobic radicaland having from 1 to 40 ethylene oxide (EO) or propylene oxide (PO)units, alkylsulfonates having C₈-C₁₈-alkyl, alkarylsulfonates havingC₈-C₁₈-alkyl, and monoesters of sulfosuccinic acid with monohydricalcohols or alkylphenols having from 5 to 15 carbon atoms, alkali metaland ammonium salts of carboxylic acids having from 8 to 20 carbon atomsin the alkyl, aryl, alkaryl or aralkyl radical, alkylphosphates andalkarylphosphates having from 8 to 20 carbon atoms in the organicradical, alkyl ether and alkaryl ether phosphates having from 8 to 20carbon atoms in the alkyl or alkaryl radical and from 1 to 40 EO units,alkyl polyglycol ethers and alkaryl polyglycol ethers having from 8 to40 EO units and from 8 to 20 carbon atoms in the alkyl or aryl radicals,ethylene oxide-propylene oxide (EO-PO) block copolymers having from 8 to40 EO or PO units, addition products of alkylamines having C₈-C₂₂-alkylradicals with ethylene oxide or propylene oxide, alkyl polyglycosideshaving linear or branched saturated or unsaturated C₈-C₂₄-alkyl radicalsand oligoglycoside radicals having from 1 to 10 hexose or pentose units,silicon-functional surfactants and mixtures of these emulsifiers. Theemulsifier content of such an emulsion is preferably from 0.01 to 5% byweight, based on the total weight of the emulsion.

In addition, an aqueous composition of a fluoroorganyl-substitutedsilicon compound used according to the invention can advantageously alsocontain customary auxiliaries selected from among inorganic or organicacids, buffer substances, fungicides, bactericides, algicides,microbiocides, odorous substances, corrosion inhibitors, preservatives,rheological auxiliaries.

The fluoroorganyl-substituted silicon compounds used according to theinvention can be present in the solid or liquid form. It is alsopossible for them to be present in a form exhibiting powder flow, inparticular pulverulent form, and be dispersible in water.

In a mixture according to the invention, the fluoroorganyl-substitutedsilicon compound can thus advantageously be present in solid formexhibiting powder flow and be supported or sorbed, in particularabsorbed, on an inorganic material, in particular a porous or absorptivematerial; this can preferably be present in the solid form exhibitingpowder flow and also be dispersible in water. It has been found that thesubstances can then be incorporated particularly well and homogeneouslyinto the mixture according to the invention.

When fluoroorganyl-substituted silicon compounds are present asparticulate or pulverulent formulations, these can be used as such or inthe form of a dispersion in the production of a mixture according to theinvention. Such particulate or pulverulent fluoroorganyl-substitutedsilicon compounds can be obtained by applying thefluoroorganyl-substituted silicon compounds according to the inventionto inorganic support materials such as metal oxides, metal carbonates,metal sulfates, metal phosphates and/or carbon blacks.

For the purposes of the present invention, metal oxides can be oxides,hydroxides or oxide hydrates of the elements of main groups I, II, IIIand/or IV and of transition groups IV, VI, VIIIa and/or VIIIc of thePeriodic Table of the Elements (PTE) and/or of cerium. Preference isgiven to using silicas such as flame silicas, i.e. pyrogenic silicas,precipitated silicas, crystalline silicas, or zeolites.

Furthermore, it is possible to use carbonates and/or hydrogencarbonatesand also sulfates and/or hydrogensulfates and also phosphates,hydrogenphosphates and/or dihydrogenphosphates of the abovementionedmetals or elements as support materials.

Furthermore, naturally occurring inorganic materials can also be used assupport materials. Such materials are, for example, clays, expandedclays, ground limestone, chalks, gypsums and/or ground rock, for exampleground shale.

Suitable particulate or pulverulent formulations, in particularformulations exhibiting powder flow, can be obtained, for example, bytreating at least one of the abovementioned support materials with atleast one of the abovementioned liquid fluoroorganyl-substituted siliconcompounds or preparations according to the invention. The treatment canbe carried out, for example, by wetting (mixing, kneading, milling,dipping, flooding) said support materials with at least one of theabovementioned fluoroorganyl-substituted silicon compound or saidpreparations and subsequently carry out a thermal after-treatment, forexample in a drying oven. However, the treatment can also be carried outby spraying the support material with a fluoroorganyl-substitutedsilicon compound, optionally at elevated temperature and optionally invapor form. The treatment is preferably carried out in a kneader, forexample a Lodige mixer. Milling and/or sifting of the powder can also becarried out beforehand or afterward. The production of suitableparticulate or pulverulent formulations can, for example, be carried outas described in the example of EP 0466958. Furthermore, suitableparticulate or pulverulent formulations can be produced as described in,for example, U.S. Pat. No. 7,514,494.

The average particle size of support materials used according to theinvention is advantageously from 1 nm to 100 μm including all numbers inbetween, preferably from 2 nm to 10 μm, particularly preferably from 3nm to 1 μm, very particularly preferably from 5 nm to 500 nm. Theaverage particle size can be determined, for example, by means oftransmission electron microscopy (TEM).

The specific surface area of support materials used according to theinvention is advantageously from 20 to 800 m²/g, including all numbersin between, preferably from 25 to 600 m²/g, particularly preferably from50 to 500 m²/g, very particularly preferably from 60 to 400 m²/g, inparticular from 70 to 300 m²/g. The specific surface area (BET) can, forexample, be determined by a method based on DIN 66131.

In addition, support materials used according to the invention canpreferably have a pore volume of from 0.1 to 10 cm³/g. The pore volumecan be calculated from the sum of micropore, mesopore and macroporevolumes. The determination of the micropores and mesopores is carriedout by recording of an N2 isotherm and evaluation thereof by the methodof BET, de Boer and Barret, Joyner, Halenda. The determination of themacropores D>30 nm is carried out by Hg porosimetry. To determine themicropores, the sample is dried for 15 hours at 100° C. in a vacuumdrying oven and degassed at room temperature under reduced pressure. Todetermine the micropores and mesopores, the sample is dried for 15 hoursat 100° C. in a drying oven and degassed for 1 hour at 200° C. underreduced pressure.

Finally, carbon blacks can also be used as support materials. As carbonblacks, it is possible to use pigment blacks having an average primaryparticle size of from 8 to 80 nm, preferably from 10 to 35 nm, and a DBPnumber of from 40 to 200 ml/100 g, preferably from 60 to 150 ml/100 g.The determination of the DBP number can be carried out in accordancewith DIN 53601 (DBP=dibutyl phthalate). As carbon blacks, it is possibleto use pigment blacks which are produced by means of furnace black, gasblack, channel black or flame black processes. Examples are Farbruβ FW200, Farbruβ FW 2, Farbruβ FW 2 V, Farbruβ FW 1, Farbruβ FW 18, Farbruβ170, Farbruβ S 160, Spezialruβ 6, Spezialruβ 5, Spezialruβ 4, Spezialruβ4A, Printex 150

T, Printex U, Printex V, Printex 140 U, Printex 140 V, Printex 95,Printex 90, Printex 85, Printex 80, Printex 75, Printex 55, Printex 45,Printex 40, Printex P, Printex 60, Printex XE 2, Printex L 6, Printex L,Printex 300, Printex 30, Printex 3, Printex 35, Printex 25, Printex 200,Printex A, Printex G, Spezialruβ 550, Spezialruβ 350, Spezialruβ 250,Spezialrull 100 from Evonik Degussa GmbH. In a preferred embodiment ofthe invention, gas blacks can be used. In a further embodiment,Si-containing carbon blacks, known from DE 196 13 796, WO 96/37447 andWO 96/37547, and metal-containing carbon blacks, known from WO 98/42778,can be used.

The particle size before or after treatment of the support material withfluoroorganyl-substituted silicon compounds or correspondingpreparations, in particular a fluoroalkylalkoxysilane or liquidfluoroalkylsilane-based systems as have been mentioned above, can beadjusted by milling, for example in a ball mill, bead mill or opposedjet mill and/or in a suitable mixing apparatus, for example a plowsharemixer. Furthermore, the particle size can be increased by suitableagglomeration processes.

If used, siliceous additives which are advantageously selected from thegroup consisting of microsilica, fly ash, flame silicas, precipitatedsilicas, zeolites, crystalline silicas, silica sols, kaolin, mica,kieselguhr, diatomaceous earth, talc, wollastonite and clay and mixturesof corresponding microsilica, fly ash, flame silicas, precipitatedsilicas, zeolites, crystalline silicas, silica sols, kaolin, mica,kieselguhr, diatomaceous earth, talc, wollastonite or clay and aqueousdispersions of at least one pyrogenic silica or at least oneprecipitated silica or a mixture of pyrogenic and precipitated silicascan be used for the purposes of the present invention.

Naturally, water is also typically present in the hydraulically settingmixture of the invention or is added thereto. The amount of water ispreferably from 1 to 20% by weight.

If the fluoroorganyl-substituted silicon compound used according to theinvention is used in the form of an aqueous preparation, it isadvantageous to take into account only the proportion of active compoundin the respective aqueous composition as fluoroorganyl-substitutedsilicon compound according to the invention for calculating the totalcomposition of the cement-bonded mixture. The water content of theseaqueous preparations is advantageously taken into account in calculatingthe amount of water which needs to be added.

Plasticizers can be all conventional flow improvers, in particularpolycarboxylate ethers (PCEs) and/or polymethyl methacrylates and alsolignosulfonates or naphthalene formaldehyde-sulfonates.

Hydraulically setting mixtures according to the invention can contain,as further auxiliaries, for example, dispersants and wetting agents, forexample siliconates or alkylphosphonates, antifoams, for exampletrialkylphosphates, air pore formers such as hydrolyzed resin acids,retarders and accelerators, for example formates, and/or water reducers.

Hydraulically setting mixtures according to the invention canadvantageously be used in the concrete industry, in which they are mixedin conventional mechanical mixers.

It can be advantageous to premix the cement and the solid aggregates,likewise premix optionally liquid, nonaqueous components with the cementand add aqueous formulations such as an aqueous dispersion or emulsionaccording to the invention of a fluoroorganyl-substituted siliconcompound, for example together with the make-up water. Pulverulentformulations can advantageously be predispersed in the make-up water.The content of additionally introduced water can advantageously be takeninto account in the setting of the desired w/c value. The processabilityof the mixtures according to the invention is advantageously unchangedcompared to unmodified mixtures.

However, it is also possible to place a solids mixture of ahydraulically setting mixture according to the invention in a mechanicalmixer and add a defined amount of water all at once or in portions andmix the whole.

Such a solids mixture according to the invention of a hydraulicallysetting mixture can be obtained, for example, by combining cement[component according to feature a], aggregate [component according tofeature b] and a support material which exhibits powder flow and havebeen treated with at least one fluoroorganyl-substituted siliconcompound [component according to feature c] in a mixing vessel, mixing,if necessary transferring to a transport container and providing it forthe application. Furthermore, plasticizers [component according tofeature d] and/or further auxiliaries [component according to feature e]can optionally be added or mixed into such a solids mixture if thesecomponents are present in powder form or a form exhibiting powder flow.Should these components according to d) and/or e) be liquid, they canlikewise be applied to one of the abovementioned support materials andin this way be converted into a form which exhibits powder flow andmixed into or added to a mixture according to the invention.

For use of such a solids mixture according to the invention (alsoreferred to as mixture for short), this can be mixed in a mixer, forexample a concrete mixer, with make-up water in a manner known per seand subsequently be used.

Furthermore, a hydraulically setting mixture according to the inventionwhich has been obtained in this way can be subjected to shaping andcuring as is known per se to a person skilled in the art to givearticles whose surfaces advantageously have, in the sense of theinvention, only a small soiling tendency (easy-to-clean property) evenin the case of abrasion.

The present invention thus also provides materials, in particularcomponents, concrete goods or moldings which can be obtained using ahydraulically setting mixture according to the invention.

The present invention further provides for the use of a hydraulicallysetting mixture according to the invention for producing materials, inparticular components, concrete goods or moldings, whose surface hasonly a small soiling tendency (easy-to-clean property) even in the caseof abrasion.

The present invention likewise provides for the use of afluoroorganyl-substituted silicon compound, in particular one asspecified in more detail above, for the body modification of ahydraulically setting mixture, in particular a mixture containing from 6to 25% by weight of cement, from 50 to 90% by weight of at least oneaggregate and from 0.001 to 8% by weight of at least onefluoroorganyl-substituted silicon compound and optionally from 1 to 20%by weight of water and/or from 0.01 to 2% by weight of plasticizerand/or from 0.01 to 1% by weight of at least one further auxiliary,where the components used in each case add up to 100% by weight.

Thus, a hydraulically setting mixture according to the invention canadvantageously be used in the building sector, in particular forproducing workpieces, for concrete paving slabs, or as facing concrete,in particular in facings for paving slabs; such workpiecesadvantageously have easy-to-clean properties.

It can be stated that the manufacturers of cement-bonded workpieces, inparticular the manufacturers of concrete slabs, have to the present dayhad great interest in lastingly modifying hydraulically setting, inparticular cement-bonded, workpieces and ensuring easy-to-cleanproperties of the surface despite abrasion and weathering effects.

The provision and use of mixtures according to the invention enables,due to the newly achieved lasting easy-to-clean properties ofhydraulically cured workpieces despite abrasion and weathering, cleaningand maintenance costs for prolonged cleaning cycles to be significantlyreduced. Such body modifications can advantageously be carried out, inparticular, in ongoing operation of a production factory and theworkpieces can be shipped in finished, protected form. An additionaloutlay on the building site is dispensed with.

However, compositions according to the invention can also be producedand advantageously used on the site of an application.

The invention is illustrated by the following examples, without thesubject matter of the invention being restricted.

EXAMPLES

The mortar test specimens used were made from a commercial universalmortar (mortar group II in accordance with DIN V 18580, mortar group PII in accordance with DIN V 18550) from Quick-Mix. For this purpose,about 100 g of the mortar was in each case intimately mixed by stirringwith about 24 ml of water. The additive indicated in each case in theexamples was predispersed in the make-up water. The mixture formed wasintroduced into PE formwork, dried at 25° C. for 24 hours, subsequentlyremoved from the formwork and cured at 25° C. for 28 days. The soilingproperties were determined by a method based on DIN EN ISO 10545-14; thetest is described in more detail below.

Amounts in % by weight are in each case based on the weight of thecomplete dry mixture.

The preparation of the fluoroalkylsilane-based additive can be carriedout as described above or in example 1 of DE 199 55 047.

Example 1 (Comparative Example)

A mortar test specimen was produced as described above. No additiveswere used.

Example 2

A mortar test specimen was produced as described above. 3% by weight ofthe aqueous fluoroalkylsilane formulation prepared as described inexample 1 of DE 19955047 was dispersed in the make-up water before itwas added.

Example 3

A mortar test specimen was produced as described above. 5% by weight ofa powder containing 6% by mass of3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyltriethoxysilane and producedas described in the example of EP 0 466 958 B1 was dispersed in themake-up water before it was added.

Example 4

A mortar test specimen was produced as described above. 10% by weight ofa powder containing 6% by mass of3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyltriethoxysilane and producedas described in the example of EP 0 466 958 B1 was dispersed in themake-up water before it was added.

Example 5

A mortar test specimen was produced as described above. 3% by weight of3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyltriethoxysilane wasdispersed in the make-up water before it was added.

Example 6 (Comparative Example)

A mortar test specimen was produced as described above. 2% by weight ofan OM emulsion containing 50% by weight (based on the total amount ofthe emulsion) of an octyltriethoxysilane was dispersed in the make-upwater before it was added.

Evaluation

Easy-to-Clean Properties:

A drop (about 0.5 ml) of each of the soiling agents coffee (black, withsugar, cold), cola, red wine and olive oil was applied to the surface ofthe cured mortar test specimen (not to the formwork side). After a timeof 1 hour at 25° C., the surface was dabbed dry with a soft cloth andrinsed with deionized water for 3 minutes. Finally, the water was dabbedoff with a soft cloth and the soiling of the surface was visuallyassessed after drying. Here, 5 means that no soiling is visible, 4 meansthat soiling is barely visible, 3 means that soiling is visible, 2 meansthat soiling is clearly visible and 1 means that soiling is veryobviously visible. Easy-to-clean properties can only be considered to bepresent when a significant improvement compared to an untreatedcomparative specimen is achieved. Very good easy-to-clean properties canbe considered to be present when the 3 aqueous soiling agents (coffee,cola, red wine) each achieve 4 or 5 and at the same time olive oilachieves a significant improvement compared to an untreated comparativespecimen. The results of the soiling test are shown In table 1.

TABLE 1 Results of the soiling test Soiling with coffee Soiling Soilingwith red Soiling with Example (with sugar) with cola wine olive oil 1 15 1 1 2 3 4 3 3 3 3 4 3 2 4 4 4 4 3 5 4 5 4 4 6 2 4 1 1

It is clear that, according to the above definition, very goodeasy-to-clean properties are achieved when using the mixtures accordingto the invention of examples 4 and 5 and good easy-to-clean propertiesare still achieved when using the mixtures according to the invention ofexamples 2 and 3. On the other hand, the comparative mixture 6, whichcontains exclusively fluorine-free alkylsilane, displays no improvementin the cleaning properties.

The invention claimed is:
 1. A hydraulically setting mixture,comprising: a) from 6 to 25% by weight of a cement; b) from 50 to 90% byweight of an aggregate selected from the group consisting of anagglomerate having a maximum particle size of 32 mm and a sand having amaximum particle size of 5 mm; and c) from 0.001 to 8% by weight of afluoroorganyl-substituted silicon compound in solid form exhibitingpowder flow and supported on an inorganic material, wherein thefluoroorganyl-substituted silicon compound is at least one selected fromthe group consisting of3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyltriethoxysilane and3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyltrimethoxysilane.
 2. Themixture of claim 1, further comprising: d) from 0.01 to 2% by weight ofplasticizers; and/or e) from 0.01 to 1% by weight of a furtherauxiliary.
 3. The mixture of claim 1, wherein the cement is at least oneselected from the group consisting of a portland cement, a compositecement, a cement having a proportion of pozzolans and a blast furnacecement.
 4. The mixture of claim 1, further comprising from 1 to 20% byweight of water.
 5. The mixture of claim 2, wherein the cement is atleast one selected from the group consisting of a portland cement, acomposite cement, a cement having a proportion of pozzolans and a blastfurnace cement.
 6. The mixture of claim 1, wherein thefluoroorganyl-substituted silicon compound is3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyltriethoxysilane.
 7. Themixture of claim 1, wherein the fluoroorganyl-substituted siliconcompound is3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyltrimethoxysilane.
 8. Themixture of claim 1, wherein the fluoroorganyl-substituted siliconcompound is a combination of3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyltriethoxysilane and3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyltrimethoxysilane.
 9. Themixture of claim 1, wherein the aggregate is an agglomerate having amaximum particle size of 32 mm.
 10. The mixture of claim 1, wherein theaggregate is a sand having a maximum particle size of 5 mm.
 11. Themixture of claim 1, wherein a content of the fluoroorganyl-substitutedsilicon compound in the mixture is from 0.003 to 5% by weight.
 12. Themixture of claim 1, wherein the fluoroorganyl-substituted siliconcompound is supported on a metal oxide, metal carbonate, metal sulfate,metal phosphate, carbon black, or a combination thereof.
 13. A processfor producing the mixture of claim 4, the process comprising admixingwater in a mixing apparatus with a mixture comprising: a) from 6 to 25%by weight of the cement; b) from 50 to 90% by weight of the aggregate;and c) from 0.001 to 8% by weight of the fluoroorganyl-substitutedsilicon compound.
 14. A material produced by the process of claim 13,said material selected from the group consisting of a concrete good anda molding.
 15. A material comprising the mixture of claim 1, saidmaterial selected from the group consisting of a concrete good and amolding.
 16. A facing concrete, comprising the mixture of claim
 1. 17. Aprocess for body modification of a cement-containing mixture, theprocess comprising: adding a fluoroorganyl-substituted silicon compoundto a cement-containing mixture, thereby forming a hydraulically settingmixture comprising: a) from 6 to 25% by weight of a cement; b) from 50to 90% by weight of an aggregate selected from the group consisting ofan agglomerate having a maximum particle size of 32 mm and a sand havinga maximum particle size of 5 mm; c) from 0.001 to 8% by weight of thefluoroorganyl-substituted silicon compound in solid form exhibitingpowder flow and supported on an inorganic material; and optionally d)from 1 to 20% by weight of water; e) from 0.01 to 2% by weight ofplasticizers; and/or f) from 0.01 to 1% by weight of a furtherauxiliary, wherein all components add up to 100% by weight, and whereinthe fluoroorganyl-substituted silicon compound is at least one selectedfrom the group consisting of3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyltriethoxysilane and3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyltrimethoxysilane.